Java实现带头结点的单链表

package cn.mrlij.linkedlist;
/***
 * 单链表的实现
 * @author dreamer
 *
 */
public class SingleLinkedList {
 public static void main(String[] args) {
 SingleLinkedListDemo s = new SingleLinkedListDemo();
 HeroNode h1 = new HeroNode(1, "宋江", "及时雨");
 HeroNode h2 = new HeroNode(3, "卢俊义", "玉麒麟");
 HeroNode h3 = new HeroNode(4, "吴用", "智多星");
 HeroNode h4 = new HeroNode(2, "林冲", "豹子头");
 s.addByOrder(h1);
 s.addByOrder(h2);
 s.addByOrder(h3);
 s.addByOrder(h4);
 System.out.println("修改前――――");
 s.list();
// HeroNode h5 = new HeroNode(4, "有用", "超星星");
// s.update(h5);
 s.del(1);
 s.del(4);
 s.del(2);
 s.del(3);
 System.out.println("删除后――――");
 s.list();
 }
 
}
class SingleLinkedListDemo{
 //创建一个头结点，初始化数据，头结点不要动，不放具体的数据
 private HeroNode head = new HeroNode(0,"","");
 //添加英雄
 public void add(HeroNode node) {
 //先找出最后的一个节点，把新加的节点放在最后一个节点的后面
 HeroNode temp = head;
 while(true) {
  if(temp.next == null) {
  break;
  }
  temp = temp.next;
 }
 temp.next = node;
 }
 public void addByOrder(HeroNode node) {
 HeroNode temp = head;
 boolean flag = false;
 while(true) {
  if(temp.next == null) {
  break;
  }
  if(temp.next.no>node.no) {
  break;
  }else if(temp.next.no == node.no) {
  flag = true;
  break;
  }
  temp = temp.next;
 }
 if(flag) {
  System.out.println("编号"+node.no+"已经存在了！");
 }else {
  node.next = temp.next;
  temp.next = node;
 }
 }
 public void update(HeroNode node ) {
 if(head.next == null) {
  System.out.println("链表为空！");
  return;
 }
 HeroNode temp = head.next;
 boolean flag = false;
 while(true) {
  if(temp == null) {
  break;
  }
  if(temp.no == node.no) {
  flag = true;
  break;
  }
  temp = temp.next;
 }
 if(flag) {
  temp.name = node.name;
  temp.nickname = node.name;
 }else {
  System.out.println("不存在该节点！");
 }
 }
 //删除节点
 public void del(int no) {
 if(head.next == null) {
  System.out.println("链表为空！");
  return;
 }
 HeroNode temp = head;
 boolean flag = false;
 while(true) {
  if(temp.next == null) {
  break;
  }
  if(temp.next.no == no) {
  flag = true;
  break;
  }
  temp = temp.next;
 }
 if(flag) {
  temp.next = temp.next.next;
 }else {
  System.out.println("该节点不存在！");
 }
 }
 public void list() {
 HeroNode temp = head;
 if(temp.next == null) {
  System.out.println("链表为空！");
  return;
 }
 while(true) {
  if(temp.next == null) {
  break;
  }
  System.out.println(temp.next);
  temp = temp.next; 
 }
 }
}
class HeroNode{
 public int no;//英雄编号
 public String name;//人名
 public String nickname;//绰号
 public HeroNode next;//下一个节点
 public HeroNode(int no, String name, String nickname) {
 this.no = no;
 this.name = name;
 this.nickname = nickname;
 }
 @Override
 public String toString() {
 return "HeroNode [no=" + no + ", name=" + name + ", nickname=" + nickname + "]";
 }
 
 
 
}